Process for extracting gold and apparatus therefor



April 1963 E. H. BENSON 3,087,611

PROCESS FOR EXTRACTING GOLD AND APPARATUS THEREFOR Filed June 2. 1959 5 Sheets-Sheet 1 Evererr H. Bens n,

Aprfl 30, 1963 E. H. BENSON PROCESS FOR EXTRACTING GOLD AND APPARATUS THEREFOR 5 Sheets-Sheet 2 Filed June 2, 1959 Evererr H. Benson, N B

April 30, 1963 E. H. BENSON PROCESS FOR EXTRACTING GOLD AND APPARATUS THEREFOR 5 Sheets-Sheet 5 Filed June 2, 1959 FIGURE 8 D IATH ERM FIGURE 9 VE OR.

FIGURE April 30, 1963 E. H. BENSON 3,

PROCESS FOR EXTRACTING GOLD AND APPARATUS THEREFOR Filed June 2. 1959 5 Sheets-Sheet 4 II [ill/111%,

FIGURE ll April 30, 1963 E. H. BENSON 3,087,611

PROCESS FOR EXTRACTING GOLD AND APPARATUS THEREFOR Filed June 2, 1959 5 Sheets-Sheet 5 FIGURE l4 United States Patent 3,087,611 PROCESS FOR EXTRACTING GOLD AND APPARATUS THEREFOR Everett H. Benson, Spokane, Wasln, assignor to liergevin & Carlson Mining and Milling Company, a corporation of Oregon Filed June 2, 1959, Ser. No. 817,525 6 Claims. (Cl. 209-4) This invention relates to a process and apparatus for extracting metals from ore, and more particularly to such a process for extracting flour gold, or gold containing a substantial amount of flour particles, by an electroamalgamatory process, from its parent ore.

An object of this invention is to provide a machine for the extraction of flour gold by causing it to form an amalgam, or physical association of some other type, with mercury.

A further object of this invention is to provide a continuous process machine for the process aforesaid of unique and novel design and construction.

A further object of this invention is to provide a dry electrical process by which flour gold becomes associated with mercury to such an extent that it is carried by the mercury.

A further object of this invention is to provide a continuous electric retort for the separation of mercury and precious metals carried thereby by distillation.

A further object of this invention is to provide a reclaimer that recovers a substantial portion of flour" mercury carried into the tailings.

The instant invention relates to a relatively narrow and specific part of the general field of ore treatment and refining, and some steps of processes and designs of parts are critical. The invention is designed to extract a flour-type gold or gold containing substantial quantities of flour particles from a pulverized ore, containing a relatively great porportion of gold, by a continuous chemical process without the destructive use of extensive quantities of either water or mercury.

The term flour gold is here used to refer to relatively small particles of gold usually of approximately colloidal dimensions, less than 250 millimicrons.

(250x centimeters) or thereabouts, but the term also includes larger particles not exhibiting true colloidal characteristics.

Flour gold has been known and probably extracted from ores, to a degree, from times immemorial. Its ex traction, for it alone and not other contained gold, has heretofore been difiicult and a trap providing with such low recovery that many relatively rich flour gold deposits and other deposits containing a substantial proportion of flour gold, particularly of western North America, have not been mined. Many of such deposits are remote from transportation and sources of water, and this has enhanced the difficulty of ore processing. The instant device is designed specifically for economical recovery of the precious metal from such deposits.

Amalgamation is an ancient and well-known process in the art of precious metal refining, and various methods of increasing probabilities of amalgamation of gold particles are well known, such as mechanical mixing, hydraulic mixing, pressurization, electrolysis, and use of various vibrators and hydraulic carriers. None of these methods have heretofore been as elfective, however, in the extraction of flour gold, as my instant invention. My investigations have revealed that much of the difiiculty heretofore experienced is caused by the physical forces brought into operation by the size of the particles involved, and thereupon I invented the present method of 3,587,611 Patented Apr. 30, 1963 ice using electrical forces to bring about amalgamation of the flour gold.

My invention possesses numerous other objects and features of advantage, some of which, together with the foregoing, will be set forth in the following description of the process and specific apparatus embodying and utilizing my methods. It should be understood that the method is applicable to other apparatus, and that the specific embodiments illustrated and described are not intended to be limiting.

In the accompanying drawings which form a part of this specification, and in which like numbers of reference refer to similar parts throughout:

FIGURE 1 is a diagrammatic representation of the apparatus of my invention showing the various steps in volved in my gold extraction process.

FIGURE 2 is a sectional view on a central vertical plane of the amalgamation cylinder.

1FilGURE 3 is an isometric view of a Teflon tailings be e.

FIGURE 4 is a cross-sectional view of the amalgamation cylinder taken through the tailings exhaust ports on the plane 4--4 of FIGURE 2 in the direction indicated by the arrows thereon.

FIGURE 5 is a similar cross-sectional view taken through the air ports on the plane 55 of FIGURE 2 in the direction indicated by the arrows thereon.

FIGURE 6 is a similar cross-sectional view taken through the brush carrier and brushes on the plane 6-6 of FIGURE 2 in the direction indicated by the arrows thereon.

FIGURE 7 is a similar cross-sectional view taken through the Teflon screw on the plane 7-7 of FIGURE 2 in the direction indicated by the arrows thereon.

FIGURE 8 is an electrical circuit diagram showing the electrostatic circuitry of my invention.

FIGURE 9 is an electrical circuit diagram showing the diathermy circuitry of my invention.

FIGURE 10 is an electrical circuit diagram showing the circuitry of the retort of my invention.

FIGURE 11 is a sectional view taken on a central vertical plane of my retort showing its internal construction.

FIGURE 12 is a cross-section of my retort taken on a horizontal plane on the line 12-12 of FIGURE 11 in the direction indicated by the arrows thereon.

FIGURE '13 is a cross-section of my retort taken on a horizontal plane on the line 13-13 of FIGURE 11 in the direction indicated by the arrows thereon.

FIGURE 14 is a central sectional view of the tailings reclaimer showing the internal structure thereof.

Referring to FIGURE 1, there is illustrated diagrammatically, the apparatus involved in my extraction process. I first prepare the ore carrying flour gold by pulverizing or otherwise breaking it into relatively small particles, preferably of such size that it will pass through a A; inch mesh screen. The crude ore is held by a hopper 20, from whence it is transferred to the amalgamation cylinder 22, through the conduit 21. The ore may be transferred through the conduit 21 by force of gravity, if the apparatus is so arranged that this is possible, or a jigger 19, shaker or mechanical conveyor may preferably be used as illustrated to regulate the flow of ore into the cylinder 22.

The amalgamation cylinder 22 is most clearly illustrated in FIGURES 2. through 7. It comprises a cylindrical outer casing 23, for mechanical support, preferably constructed from cast iron and containing through a part of its length an inner cylindrical casing 24- preferably coustructed from copper. The material of the outer casing 23 is not critical. The rearward or exhaust end of the cylinder 22 is covered by the cap 25, which is fastened in place to the outer casing 23 by the bolts 26. The interior of the outer casing 23 is shaped substantially as illustrated with a concentrically located screw chamber 27 at its forward end and a somewhat larger concentrically located brush chamber 28 at its rearward end. It is this brush chamber 28 that is lined with the relatively thin cylindrical inner casing 24, preferably constructed from copper, though it may be constructed from some other metal that will form an amalgam with mercury or the surface of which will be wet by mercury. I prefer to press-fit the inner casing 24 within the outer casing 23, though it may be secured by other means.

An ore intake port 29 communicates from the hopper conduit 21, through the outer casing 23, to the screw chamber 27 near the forward-most portion thereof, thus allowing ore to flow into the forward part of the screw chamber. A jigger 19, or other variable regulating device, is placed at this port to regulate the flow of ore to the screw chamber 27. A mercury intake port 30' communicates with the screw chamber 27 through the outer casing 23 immediately to the rearward of the ore intake port 29.

Toward the rearward portion of the brush chamber 28, several air ports 31 are constructed through both the inner casing 24 and on the lowermost quadrant thereof. Immediately rearward of these air ports 31 is an annular shoulder 32 fastened on the inner surface of the inner casing 24. To the rearward of this shoulder 32 is the tailings exhaust part 33.

concentrically carried within the amalgamation cylinder 22 is the central shaft 34 riding in the thrust hearing 35 in the cap 26 at its rearward end and being rotatably carried within the bearing 36 in the outer casing 23 at its forward end. On this central shaft 34, at its forward end portion passing through the screw chamber 27, is carried the Teflon screw 37. To the rearward, in the brush chamber 28, is carried brush carrier 43 with brushes 38 and at the rearward end portion of the shaft 34 is carried the Teflon tailings bafile 39.

The screw 37 is preferably a square threaded screw having an external diameter slightly less than the internal diameter of the screw chamber 27, to allow for the diathermy coil 89, and of a length substantially the same as the screw chamber 27. The pitch of the screw 37 is not critical so long as it fulfills its purpose of mixing ore and mercury in the screw chamber 27 and moving the mixture rearward into the brush chamber 28. The screw 37 is bored to receive the central shaft 34 and is adapted to be irrotatably carried thereon by bolting the flange 40 at its rearward end to the collar 41, about the central shaft 34, which collar 41 is in turn keyed with the key 42 to the central shaft 34. I prefer to construct this screw 37 of a plastic material manufactured by Du Pont de Nemours and Co., Inc., known as Teflon because of its easy machinability, great resistance to wear and abrasion and high dielectric properties and strength, but other materials having similar properties would serve the purposes of my invention.

I prefer to use six double row brushes 38 in my device, though the number or type is not critical. The brushes 38 are mounted on a high dielectric plastic brush carrier 43 which in turn is irrotatably carried upon the central shaft 34. I mount the brushes 38 in an equally spaced fashion around the circumference of the carrier 43, but with a slight angle or lead of some fifteen degrees or so, in the rearward direction so that when the brushes rotate, matter in the brush chamber will be given not only a rotary motion but will also be forced slowly to the rear of the brush chamber 28. The brushes 38 have bristles 44, preferably again of a high dielectric plastic, of such length that they just touch the inner surface of the inner casing 24 of the brush chamber 28. These brushes may be mounted by any of the well-known adjustable methods which provide compensation for bristle wear and thereby lengthen the effective brush life. All but one of my brushes 38 extend to the forward end of the tailings bafide 39, and the other 38-a extends through appropriately positioned channel 45 in the tailings bafile 39 to the end of the brush chamber 28. The purpose of this one longer brush 38a is to provide means of moving the tailings in the brush chamber 28 to the rearward of the shoulder 32, to the exhaust port 33, where it may be expelled or conveyed to the tailings reclaimer 55.

The tailings bafi'le 39 is constructed substantially as illustrated in FIGURE 2, with a forward annular portion 46 having an external surface 48 shaped as the frustrum of a right cone flaring outward in the forward direction and a rearward disk-like baffle portion 47. The forward annular portion 46 of the bafile 39 must be so designed and positioned as to have the external angular face 48 positioned adjacent to the air ports 31 to serve the function required of the part. The baffle 39 is drilled to be mounted on the central shaft 34 and is irrotatably carried thereon by means of an appropriate key 74. I again prefer to construct this member 39 from Teflon for the reasons hereinbefore set forth for the screw 37, but other like material will also serve the purposes of my invention.

The central shaft 34 is activated by an appropriate prime mover 49 which imparts a rotary motion to it. I prefer to use a variable speed electric motor as a prime mover but motors of other types will serve the purposes of my invention.

Compressed air is supplied to the air port 31 by the compressor 50, through the storage tank Stl-a, through the conduit 51 and the continuously variable valve 52. Compressed air is also supplied by the same source 50, a through the conduit 53 and continuously variable valve 54 to the tailings reclaimer 55.

Amalgam and mercury leave the amalgamation cylinder 22 through the air port 31 and is conducted by gravity through the conduit 56 into the trap 57, thence to the mercury storage reservoir 58 where the amalgam is stored until it can be refined. A by-pass conduit 59 is provided from the bottom of the trap 57 directly to the retort 60; mercury passage in this line 59 also is caused by gravity and is controlled by the valve 62. This bypass system is used when the machine is stopped or shut down from continuous operation to convey gold rich amalgam and mercury in the trap directly into the crucible 61 of the retort 60.

The retort 60 is a cylindrical structure, having a substantially vertically orientated axis, comprising an upper member 63 or cap, a middle member 64 or body, and a bottom member 65 containing a crucible 61. These members 63, 64, 65 are constructed preferably from cast iron as illustrated in FIGURE 11 with flanges to provide for their attachment to each other by bolting, as illustrated. Mercury and amalgam enter from the conduit 56 into the intake chamber 66 in the middle member 64, from whence the product passes into the relatively smaller spiral conduit 67 and therethrough into the crucible 61. The spiral conduit 67 is formed into a cylindrical spiral of such dimensions as will fit within the heating coils, and it should be of such length that by the time the mercury and amalgam pass therethrough they will be preheated to a temperature near the point of vaporization. The bypass conduit 59 enters into the retort 60 in the lower portion of the middle member 64 to permit amalgam to pass by gravity directly into the crucible 61.

Electrical resistance heating elements 68, of the ordinary variety well known in commerce, are formed into a circular shape so as to fit about the inner surface of the retort 60, and spaced therein throughout the length of the retort 60. These elements 68 are individually controlled as hereinafter specified. The number of heating elements 68 must be regulated so as to give sufiicient heat to vaporize mercury and keep it vaporized until the vapor leaves the retort. Any gold contained in amalgam being distilled will be left in the crucible 61 and may be removed from the retort 60 by unbolting and removing the bottom member 65. The outside of the retort 60 should be covered with a thermal insulation 91 to prevent excessive heat loss therefrom.

The vapors of the distilled mercury pass from the retort 60 through the port 69 and thence through the conduit 70 into the condenser 71. This condenser 71 is of the type well known in the art. The condensed mercury then flows by gravity through the conduit 72 to the reservoir 73 where it is stored until needed again in the amalgamation cylinder 22. When again needed, the mercury flows from the reservoir 73, through the conduit 74 and variable valve 75, through the mercury intake port 29 and again into the cylinder -22.

The tailings from the exhaust port 33 are gathered in the collector 94 and pass through the conduit 92 into the tailings reclaimer 55, near the upper portion thereof as illustrated. The reclaimer 55 consists of an upright pot 75, preferably constructed of iron with a tailings inlet port 76 in the upper portion thereof and a tailings exit port 77 on the opposite side somewhat below the level of the inlet port 76. The bottom of the pot 75 is provided with a mercury exit port 78 through which recovered mercury and amalgam flow into the conduit 79 and therethrough to the conduit 80 from whence it recycles into the retort 60 for distillation. A trap 85 is provided in the conduit 80 to prevent water from entering the conduit and thereby passing into the retort 60.

The reclaimer pot 75 has a false bottom 81 upon which is supported a filling of copper shavings 82, which should fill the pot to a level above the tailings inlet port 76. The false bottom 81 is preferably constructed with holes or perforations, but they must be of such size as to prevent the copper shavings 82 from passing therethrough. The size or shape of the copper shavings is not particularly material. I prefer to obtain them by turning a copper rod with an ordinary V-shaped lathe tool.

The reclairner pot 75 is filled with water to a level above that of the copper shavings from some external source 83, and compressed air is supplied to the pot 75 by the compressor 50 through the conduit 53. The compressed air is introduced into the pct 75 through the multi-hole nozzle 84 at a level only slightly above the false bottom 81, to cause aggitation of the tailings within the pot 75. The exhausted tailings leave the exit port 77 and are conveyed away as waste.

The electrical circuitry of my invention is illustrated in FIGURES 8, 9, and 10.

A high voltage direct current potential, on the order of 70,000 volts, is maintained between the central shaft 34 and the interior walls of the amalgamation cylinder 22. This potential value is somewhat critical, but varies with different ores, and must be determined empirically for each ore for maximum recovery. The impressed electrical potential must therefore be variable within limits.

I regulate the voltage in my electro-static circuit by means of a resistance type voltage regulator 98. I use an oil immersion transformer 96 to raise ordinary commercially available alternating current to the desired higher voltages, and I then rectify this current in a tube-type rectifier 97 to give the desired high voltage direct current. This current is supplied to my device so that the central shaft 34 constitutes the anode of the circuit and the cylinder 22 constitutes the cathode or negative side of the circuit. Any of the other well known methods of producing high voltage direct currents will serve the purpose of my invention equally well, as the only essential is the end electrical product and not the means.

I also use a diathermy current in the screw chamber 27 to assist in mixing and amalgamating the mercury and flour gold. This current is generated by the ordinary diathermy machine 88 of commerce in frequencies which range from 1.5 to 0.5 million cycles per second. The

6 diathermy current is applied within the screw chambe 27 through the cylindrical spiral coil 89 designed and adapted to fit about the inner wall of that chamber 27. The exact frequency of the diathermy current giving best recovery again varies with different ores, and must be arrived at in a specific instance empirically.

As illustrated in FIGURE 10, each of the resistance heating elements 68 in the retort 60 is separately controlled by thermostats 90. These thermostats 90 are of the type well known in the art, that have an elongate temperature sensing probe that is adapted to function in the appropriate heat range wherein mercury remains a vapor. The thermostat 90 for each element is positioned at the level of the element controlled, and with the elongate temperature sensing probe projecting inwardly through the outer walls of the retort 60. By this arrangement a uniform or graduated heat may be maintained in the retort as desired. I prefer to design the heating elements to operate on a 220 volt single phase alternating current, but this is in no way critical so long as sufficient heat is supplied.

To process a flour gold containing ore, it is first pulverized preferably so as to pass a /8 inch screen. The pulverized ore is stored in the hopper 20 from whence it is fed as needed, into the screw chamber 27 of the amalgamation cylinder 22. Mercury is fed into the screw chamber 27 through the intake port 30 and is physically mixed with the pulverized ore in the chamber 27 by the rotary motion of the screw 37, while the mixture is at the same time moved rearward through the screw chamber 27 and into the brush chamber 28.

1 have found that my process loses efficiency in the recovery of gold values unless the ore is reasonably well pulverized. The quantity of mercury fed into the screw chamber 27 must be in excess of the amount necessary to form a liquid amalgam with any gold present, but so long as this minimum is met the relative ratio of mercury to ore in the screw chamber 27 seems not to be critical, except that to a certain point an increase in mercury will increase the probabilities of amalgamation of flour gold present. As the ore-mercury mixture is mixed and passed through the screw chamber 27, it is acted upon by a diathermy current provided in the coil 89 about the screw chamber 27. The diathermy current may be varied in frequency through a limited range; the exact frequency giving the greatest relative recovery must be determined empirically by analysis of raw ore and recovered gold. The reason of the diathermy currents benefiting the recovery in my process is not presently known with any certainty. Apparently however, it aids in causing some type of a physical mixture of mercury and flour gold particles as optical analysis indicates particles of flour gold on the surface of mercury globules, rather than being intimately mixed as in a true amalgam.

For convenience herein, however, the mixture of mercury and gold, no matter what be its true nature, is referred to as an amalgam.

The mercury-ore mixture is passed through the screw chamber 27 and into the brush chamber 28. Here the mixture is moved and rubbed about the inner surface of the copper inner casing 24 by the rotary action of the brushes 38, and at the same time is slowly moved rearward in the brush chamber 28 by the slight screw action of the brushes 38.

As the mercury-gold mixture is passed over the inner surface of the inner casing 24, an amalgam or other type of deposit of the mercury-gold mixture is formed on the inner surface of the copper. Only a part of the mercury introduced into the amalgamation cylinder 22 is thus deposited on the inside of the inner casing 24, however. As this mercury-gold deposit builds up on the walls of the inner casing 24, it is forced toward the rearward of the brush chamber 28 by the screw action of the brushes 3'8 rubbing against it, and finally arrives at the air ports 31.

During this process in both the screw chamber 27 and brush chamber 28, a relatively high electric potential is maintained between the central shaft 34 and the inner surface of both chambers 27, 28. I find that a potential of about 70,000 volts results in the best recovery with most ores, though this may vary with different types of ore and sizes of particles. The central shaft 34 must be the anode and the surface of the chambers 27, 28, the cathode to assist the amalgamation process. Flour gold constitutes relatively small particles, and as such they are known to have relatively great positive electro-static charges for their size. These small particles have a tendency to remain suspended in the air by reason of Brownian movements, or the like, or at least react very slowly to the force of gravity, and tend not to break the surface tension of mercury. The potential between the central shaft and the inner chamber walls 27, 28 causes a substantial electromotive gradient exerting a considerable force on any floating or unamalgamated positively charged gold particles within the amalgamation cylinder 22, forcing them to the inner cylinder Walls where they break the surface tension of the mercury or amalgam there present and become amalgamated therewith.

A major portion of the mercury introduced into the amalgamation cylinder 22 is not deposited on the inner walls of the brush chamber 28, but rather arrives at the air ports in the form of globules of gold-mercury amalgam, mixed with the expended powdered ore. This mixture is moved to the air ports 31 by the screw action of the brushes 38. At the same time air, under pressure, is introduced through the air ports 31. The air pressure is so regulated by the valve 52 that it is not suflicient to prevent the relatively heavy mercury globules from passing downward through the air ports 31 when acted upon the force of gravity, but is suflicient to raise the lighter powdered ore against the annular shoulder 46 of the tailings baflle 39 and thereby deflect it rearward over the shoulder 32 from which it passes through the tailings exhaust port 33.

The gold bearing mercury passes by gravity through the air port 31, through the conduit 56, through the trap 57 where any unusually rich amalgam is retained, and into the storage reservoir 58. The gold-bearing mercury is then passed by gravity at a predetermined rate into the retort 60.

The amalgam enters the retort 60 at the intake chamber 66 in the upper portion thereof, and then passes into the spiral conduit 67 and therethrough into the crucible 61. The retort chamber is maintained at a temperature above the boiling point of mercury, so by the time the amalgam passes into the crucible 61 it is at or near its boiling point and thereafter vaporizes within a relatively short time. Any gold or other non-volatile impurities in the amalgam will be left in the crucible 61, .and the mercury vapors pass upward and out through the exit port 69, thence through the conduit 70, and into the condenser 71, from whence the mercury passes by gravity, or may be pumped if necessary, into the storage reservoir 73, where it awaits to be recycled back through the amalgamation cylinder 22.

The expended tailings passing out through exhaust port 33 contain a small residual of mercury, primarily in very fine globules commonly known as flour mercury, and this mercury may contain some gold. The tailings are therefore passed through a reclaimer 55 to recover such residual contained mercury and gold as is possible to recover. The tailings are carried by gravity from the exhaust port 33, through the conduit 92, and to the reclaimer 55. The tailings enter the reclaimer 55 through the port 76, below the level of the water therein, and are intimately mixed about the copper shavings 82 by the action of compressed air bubbling therethrough. During the process, a substantial part of any residual mercury becomes amalgamated on the surface of the copper shavings -82 while the remainder of the tailings pass out of the reclaimer 55 through the exit port 77 and thence out to waste. The amalgam, and any contained gold, as it builds up on the copper shavings, tends to pass to the bottom of the reclaimer 55 by the action of gravity, and thence through the false bottom 81, through the exit port 78, the trap and thence back into the retort 60 for distillation. The trap 85 is designed to prevent any water from entering the mercury conduit 79.

When the reclaimer 55 is in operation a continuous flow of water is preferably provided from the source 83 to maintain the water level as aforesaid, and to carry excessive tailings from the exhaust port 77. The exhaust line is preferably provided with an ordinary plumbers trap or similar device (not shown) well known in the art to conveniently maintain the reclaimers water level as aforesaid.

It is to be noted that water or tailings will not pass from the exit port 78 as both float on top of the level of amalgam maintained in the bottom of the reclaimer 55 by the trap 85.

Although the foregoing description is necessarily of a detailed specific character in order that as specific embodiment of my invention may be set forth, it is to be understood that the specific terminology and structure are not intended to be restrictive or confining, and that various rearrangement of parts or steps and modifications of detail may be resorted to without departing from the essence, scope or spirit of the invention herein set forth.

Having hereby described my invention, what I desire to protect by Letters Patent and,

What I claim is:

l. A process for the extraction of flour gold and gold containing flour particles from parent ores, comprising the steps of pulverizing the gold-bearing ore, physically mixing the pulverized ore with mercury within the field of a cylindrical spiral coil subjected to diathermy current, passing said ore-mercury mixture over an amalgamated internal cylindrical surface having a relatively great electro-static potential gradient between the anode center and cathode surface thereof; physically separating said admixed mercury and gold from said ore, and separating said mercury and contained gold by distillation to recover the respective fractions.

2. In a process for the amalgamation of flour gold and gold containing flour particles, the steps of pulverizing the gold-bearing ore and physically mixing said pulverized ore with mercury within the field of a cylindrical spiral coil subjected to a diathermy current, said coil being contained in 'a cylinder-like structure having an electro-static potential gradient from an interior axial anode to an exterior cylindrical cathode.

3. A machine for the amalgamation and recovery of flour gold and gold containing flour particles, comprising in combination, an amalgamation cylinder having a forward screw chamber with an ore port and a mercury port communicating with the forward portion thereof and with a screw axially aligned and rotatably carried therein and a diathermy coil thereabout; a rearward brush chamber communicating therewith having an interior lining of metal wetable by mercury, an axially aligned rotatably carried cylindrical brush therein adapted to rotatably and axially move material therethrough, an air inlet port near the rear portion thereof, an inwardly projecting shoulder immediately rearward of said air inlet port, a baflle adjacent said air port adapted to direct air flow rearward and over said shoulder, and a tailings exit port to the rearward of said shoulder; means of imparting directional motion to said screw and said brush; means of supplying pres urized air to said air inlet port; means of applying diathermy current to said diathermy coils; and means of creating an electro-static potential between an axially aligned anode within said amalgamation chamber and said chamber walls: a continuous electric retort communicating therewith having an elongate vertical cylinder with an amalgam input port in the upper portion thereof, a relatively smaller spiral conduit communicating therewith and descending therefrom, a crucible removably carried in the bottom of said retort adapted to receive amalgam from said spiral conduit and hold contained gold, a plurality of individually thermostatically controlled electric resistance heating elements about the inner wall of the retort cylinder adapted to maintain said retort chamber at a predetermined temperature sufficient to vaporize mercury, a mercury vapor port communicating with said retort chamber at the upper part thereof; means of condensing said mercury vapor and means of supplying electric current to said heating elements: a reclairner communicating therewith having a pot with -a tailings input port in the upper portion thereof, a tailings exit port in the opposite side below said input port, a mercury exit port in the bottom thereof, and a perforated false bottom therein; copper shavings resting on said false bottom and filling said pot above said input port; water filling said pot to a level above said copper shavings; means of bubbling compressed air therethrough; means of supplying water thereto; and means of preventing water from leaving said pot.

4. In a machine for the amalgamation and recovery of flour gold and gold containing flour particles, in combination, an amalgamation cylinder having a forward screw chamber with an ore port and a mercury port communicating with the forward portion thereof and with a screw axially aligned and rotatably carried therein and a diather-my coil thereabout; a rearward brush chamber communicating therewith having an interior lining of metal wetable by mercury, an axially aligned rotatably carried cylindrical brush therein adapted to rotatably and axially move material therethrough, an air inlet port near the rear portion thereof, an inwardly projecting shoulder immediately rearward of said air inlet port; a baffle adjacent said air port adapted to direct 'air flow rearward and over said shoulder, and a tailings exit port to the rearward of said shoulder; means of imparting directional motion to said screw and said brush; means of supplying pressurized air to said air inlet port; means of applying diathermy current to said diathermy coils; and means of creating an electro-static potential between an axially aligned anode within said amalgamation chamber and said chamber walls.

5. In a machine for the amalgamation of flour gold and gold containing flour particles a continuous electric retort for the distillation of mercury comprising, in combination, an elongate vertical cylinder having an amalgam input port in the upper portion thereof, a relatively smaller spiral conduit communicating therewith and de scending therefrom, a crucible removably carried in the bottom of said retort adapted to receive amalgam from said spiral conduit and hold contained gold, a plurality of individually thermostatically controlled electric resistance heating elements about the inner wall of the retort cylinder adapted to maintain said retort chamber at a predetermined temperature sufficient to vaporize mercury, a mercury vapor port communicating with said retort chamber at the upper part thereof; means of condensing said mercury vapors and means of supplying electric current to said heating elements.

6. In a machine for the amalgamation and recovery of flour gold and gold containing flour particles, in combination, a reclaimer having a, pot with a tailings input port in the upper portion thereof, a tailings exit port in the opposite side below said input port, a mercury exit port in the bottom thereof, and a perforated false bottom therein; copper shavings resting on said false bottom and filling said pot above said input port; water filling said pot to a level above said copper shavings; means of bubling compressed air therethrough; means of supplying water thereto; and a trap providing means of preventing water from leaving said pot.

References Cited in the file of this patent UNITED STATES PATENTS 785,522 Robinson Mar. 21, 1905 858,456 Heisel July 2, 1907 1,000,086 Goetz et al. Aug. 8, 1911 1,070,048 Loucks Aug. 12, 1913 1,627,181 Keith May 3, 1927 2,362,718 Pidgeon Nov. 14, 1944 2,426,148 Hyb-inette et al. Aug. 19, 1947 2,814,477 Loomis et al. Nov. 26, 1957 

1. A PROCESS FOR THE EXTRACTION OF FLOUR GOLD AND GOLD CONTAINING FLOUR PARTICLES FROM PARENT ORES, COMPRISING THE STEPS OF PULVERIZING THE GOLD-BEARING ORE, PHYSICALLY MIXING THE PULVERIZED ORE WITH MERCURY WITHIN THE FIELD OF A CYLINDRICAL SPIRAL COIL SUBJECTED TO DIATHERMY CURRENT, PASSING SAID ORE-MERCURY MIXTURE OVER AN AMALGAMATED INTERNAL CYLINDRICAL SURFACE HAVING A RELATIVELY GREAT ELECTRO-STATIC POTENTIAL GRADIENT BETWEEN THE ANODE CENTER AND CATHODE SURFACE THEREOF; PHYSICALLY SEPARATING SAID ADMIXED MERCURY AND GOLD FROM SAID ORE, AND SEPARATING SAID MERCURY AND CONTAINED GOLD BY DISTILLATION TO RECOVER THE RESPECTIVE FRACTIONS. 